Catalytic Co-Combustion of Peat and Anthracite in a Fluidized Bed

Abstract

The catalytic combustion of peat, anthracite, and their mixture in a ratio of 40 : 60 wt % was studied. The addition of peat with a high yield of volatiles to anthracite increased the degree of burnout of the mixture. When the commercial aluminum-copper-chromium oxide catalyst IK-12-70 was used (bed height 1 m, process temperature 700–750°C, particle size of solid fuel less than 1.25 mm), the degree of burnout was 98.2% (peat), 50.9% (anthracite), and 74.2% (peat–anthracite mixture). For large particles of a shaped peat–anthracite mixture with an equivalent diameter of 11.6–18.6 mm, burnout in the upper part of the fluidized bed of the catalyst was 80.5%. The degree of burnout of large particles fed into the lower part of the fluidized bed was evaluated taking into account the degree of burnout of small particles that passed the bed. When large particles of the shaped peat–anthracite mixture were fed, burnout reached at least 95% at a temperature of 700–750°C and a catalyst bed height of 1 m. To avoid accumulation of ash particles in the fluidized bed, the particle size of peat and anthracite in the shaped fuel should not exceed 1–1.5 mm when using a catalyst with a particle size of 2 mm.